A 3D printed Cu evaporator support for record-high interfacial solar evaporation

Interfacial solar evaporation offers a sustainable route for seawater desalination, addressing global freshwater scarcity by harnessing solar energy for efficient water evaporation. However, its performance is typically constrained by the availability and intensity of sunlight. Here, we report a novel evaporator design that overcomes this limitation by extracting substantial thermal energy from the bulk water to sustain high evaporation rates even in the absence of solar input. Through rational structural design and optimization of thermal conductivity of the evaporator support, the obtained evaporators harvest energy from the bulk water far exceeding the incident solar flux, enabling rapid evaporation under diverse weather conditions. The optimized evaporator achieves an exceptional evaporation rate of 11.15 kg m^-2 h^-1 under 1.0 sun. This design strategy expands the operational window of interfacial solar evaporation and offers a robust pathway toward continuous, high-efficiency desalination in real-world environments.